UNIVERSITY   OF   CALIFORNIA 

COLLEGE    OF    AGRICULTURE 

AGRICULTURAL   EXPERIMENT   STATION 

BERKELEY,    CALIFORNIA 


A  STUDY  OF  THE  RELATIVE  VALUE 

OF  CERTAIN  ROOT  CROPS  AND 

SALMON  OIL  AS  SOURCES 

OF  VITAMIN  A  FOR 

POULTRY 


D.  E.  DAVIS   AND  J.  R.  BEACH 


BULLETIN  412 

NOVEMBEK,   1926 


UNIVERSITY  OF  CALIFORNIA  PRINTING  OFFICE 

BERKELEY.  CALIFORNIA 

1926 


Digitized  by  the  Internet  Archive 

in  2012  with  funding  from 

University  of  California,  Davis  Libraries 


http://www.archive.org/details/studyofrelativev412davi 


A  STUDY  OF  THE   RELATIVE  VALUE  OF  CERTAIN 

ROOT  CROPS^  AND  SALMON  OIL  AS  SOURCES 

OF  VITAMIN  A  FOR  POULTRY 

D.  E.  DAVIS2  AND  J.  E.  BEACH3 


In  1925  Davis  and  Beach*  reported  studies  of  the  relative  value, 
as  sources  of  vitamin  A  for  poultry,  of  several  succulent  feeds.  The 
only  root  crops  included  were  a  small  sized  market  variety  (exact 
variety  unknown)  of  carrots  and  one  variety  of  mangel  beets.  The 
carrots  proved  to  be  as  good  a  source  of  vitamin  A  as  green  barley, 
alfalfa,  clover,  etc.,  but  the  mangel  beets  were  apparently  worthless. 

The  purpose  of  this  experiment  was  to  determine  if  other  varieties 
of  root  crops  which  give  a  larger  yield  than  the  variety  of  carrots 
used  in  the  previous  experiments  would  provide  a  sufficient  amount 
of  vitamin  A  to  make  them  satisfactory  substitutes  for  green  food  in 
poultry  rations. 

Since  vitamin  A  is  commonly  associated  with  the  pigments, 
xanthophyll,  chlorophyll,  and  carotin,  color  was  the  basis  upon  which 
the  selection  of  varieties  of  roots  used  was  made.  All  varieties  of 
carrots,  mangel  beets,  and  turnips  that  are  grown  to  any  extent  in 
this  state  were  roughly  classified  as  red,  yellow,  or  white.  For  use 
in  these  tests  one  variety  of  carrots,  beets,  or  turnips  was  selected 
as  representative  of  all  varieties  of  that  color  class. 

The  varieties  selected  were  as  follows : 

Yellow  Giant  carrot,  representing  the  yellow  carrots. 

Danvers  Half  Long  carrot,  representing  the  red  carrots. 

White  Belgian  carrot,  representing  the  white  carrots. 

Mammoth  Long  Red  mangel,  representing  the  red  mangels. 

Golden  Tankard  mangel,  representing  the  yellow  mangels. 


1  Tests  of  the  roots  used  were  carried  out  with  the  cooperation  of  G.  W. 
Hendry,  Division  of  Agronomy,  University  of  California,  who  has  made  cultural 
studies  of  California  root  crops.  Mr.  Hendry  classified,  selected,  and  provided  all 
roots  used  in  these  trials. 

Those  desiring  information  regarding  yield,  adaptability  for  any  section  of 
the  state,  etc.,  are  referred  to  G.  W.  Hendry,  College  of  Agriculture,  University  of 
California,  Berkeley,  Calif. 

2  Junior  Veterinarian  in  the  Experiment  Station. 

3  Assistant  Professor  of  Veterinary  Science,  Associate  Veterinarian  in  the 
Experiment  Station. 

4  Davis,  D.  E.,  and  J.  E.  Beach.  A  study  of  the  relative  values  of  certain 
succulent  feeds  and  alfalfa  meal  as  sources  of  vitamin  A  for  poultry.  California 
Agr.  Exp.  Sta.  Bui.  384:1-14.     fig.  1.     1925. 


4  UNIVERSITY    OP    CALIFORNIA EXPERIMENT    STATION 

Half  Sugar  mangel,  representing  the  white  mangels. 

American  Purple  Top  Swede  turnip,  representing  the  yellow  or 
rutabaga  turnips. 

Purple  Top  White  Globe  turnip,  representing  white  turnips. 

Fish  oils  in  general  have  been  found  to  contain  vitamin  A,  but 
cod-liver  oil  is  the  one  commonly  used.  Salmon  oiP  is  available  in 
large  quantities  on  the  Pacific  coast,  and  is  less  expensive  than 
cod-liver  oil.  It  was,  therefore,  thought  worth  while  to  determine 
if  this  oil  would  make  a  satisfactory  substitute  for  cod-liver  oil  as  a 
source  of  vitamin  A  for  poultry. 

PLAN    OF   THE    EXPERIMENT 

The  general  plan  of  the  experiment  was  to  feed  fowls  a  basal 
ration  which  previous  experiments^-  "^  had  shown  to  be  deficient  in 
vitamin  A  and  to  supplement  this  with  different  varieties  of  mangels, 
carrots,  and  turnips  or  salmon  oil.  The  basal  ration  was  a  dry  mash 
mixture,  consisting  of  25  per  cent  each  of  bran,  shorts,  and  ground 
barley,  10  per  cent  of  soybean  meal  and  15  per  cent  of  meat  scrap, 
which  was  constantly  before  the  birds  in  hoppers,  and  a  scratch  grain 
mixture,  consisting  of  equal  parts  of  wheat,  barley,  and  white  Egyp- 
tian corn,  which  was  fed  twice  .daily  in  the  litter.  Shell  was  available 
at  all  times. 

The  birds  were  confined  in  houses  which  had  tight  board  floors 
covered  with  shavings  for  litter.  A  weighed  amount  of  a  supplement 
was  fed  daily,  except  Sunday,  to  each  bird. 

The  supplements  were  fed  in  a  specially  constructed  coop.^  Birds 
which  did  not  voluntarilj^  consume  all  of  their  daily  supply  were 
forcibly  fed  the  remainder.  The  finely  chopped  carrots,  mangels,  and 
turnips  were  placed  in  cups  suspended  on  the  sides  of  the  feeding 
coop.  The  salmon  oil  was  introduced  into  the  esophagus  with  a 
pipette. 

One  hundred  pullets,  all  of  which  were  from  the  same  brood  of 
chicks,  were  divided  into  ten  groups  of  ten  birds  each  when  three 
months  of  age  and  supplied  the  basal  ration  and  an  abundance  of 
green  food.     The  purpose  of  this  was  to  have  them  all  in  as  nearly 


5  The  manufacturers  who  supplied  the  oil  stated  that  it  was  extracted  from 
salmon  cannery  refuse  consisting  of  heads,  tails,  fins,  and  viscera,  including  the 
liver,  and  contained  not  more  than  4.16  per  cent  free  fatty  acid. 

6  Beach,  J.  E.  Studies  on  a  nutritional  disease  of  poultry  caused  by  vitamin  A 
deficiency.     California  Agr.  Exp.  Sta.  Bui.  378:1-22.     figs.  1-7.     1924. 

7  Davis,  D.  E.,  and  J.  E.  Beach,  op.  cit.,  p.  4. 

8  Davis,  D.  E.,  and  J.  E.  Beach,  op.  cit.,  p.  5.     fig.  1. 


BUL.  412 


A   STUDY   OF   SOURCES  OF   VITAMIN  A   FOR  POULTRY 


5 


the  same  condition  as  possible  when  the  experimental  feeding  was 
started.  On  October  19,  when  the  pullets  were  four  months  of  age, 
they  were  leg-banded  and  experimental  feeding  was  begun  as  indi- 
cated in  table  1. 

TABLE   1 


Group  No. 

Bird  No. 

Ration 

I 

1-10 

Basal  ration  plus  Yellow  Giant  carrot 

II 

11-20 

Basal  ration  plus  Mammoth  Long  Red  mangel 

III 

21-30 

Basal  ration  plus  Danvers  Half  Long  carrot  (red) 

IV 

31-40 

Basal  ration  plus  Golden  Tankard  mangel  (yellow) 

V 

41-50 

Basal  ration  plus  White  Belgian  carrot 

VI 

51-60 

Basal  ration  plus  Half  Sugar  mangel  (white) 

VII 

61-70 

Basal  ration  plus  American  Purple  Top  Swede  turnip  (yellow) 

VIII 

71-80 

Basal  ration  plus  Purple  Top  White  Globe  turnip 

IX 

91-100 

Basal  ration  plus  salmon  oil 

X 

101-110 

Basal  ration  only.     Control  pen 

At  the  beginning  of  the  experiment  the  daily  amount  of  supple- 
ment, except  salmon  oil,  was  arbitrarily  fixed  at  one  gram^  to  a  bird. 
The  amount  of  salmon  oil  was  one  cubic  centimeter.  The  daily  amount 
of  any  supplement  was  doubled  for  all  birds  in  a  group  whenever 
any  bird  in  that  group  exhibited  definite  indications  of  vitamin  A 
deficiency.  The  amount  of  the  supplement  was  again  doubled  when- 
ever the  condition  of  the  birds  indicated  that  they  were  still  getting 
an  insufficient  amount  of  vitamin  A.  The  appearance  of  either  the 
characteristic  ophthalmia,  or  pustules  in  the  mouth  or  esophagus, 
described  by  Beach,^"  was  regarded  as  a  definite  indication  of  vita- 
min A  deficiency. 

9  A  record  of  the  mash  and  grain  consumption  was  kept  in  order  to  determine 
what  percentage  of  the  total  food  consumption  the  supplement  constituted.  The 
average  daily  consumption  to  a  bird  over  the  period  of  ninety-six  days  in  groups 
I  and  III,  the  only  groups  in  which  no  birds  died  from  any  cause,  was  fifty-nine 
grams  of  mash  and  thirty-six  grams  of  grain.  Calculated  on  the  basis  of  this 
average  (ninety-five  grams  daily)  the  percentage  of  supplement  in  the  total 
amount  of  feed  consumed  was  as  follows : 

One  gram  of  supplement  daily 1.0  per  cent  of  the  total  ration 

Two  grams  of  supplement  daily 2.0  per  cent  of  the  total  ration 

Four  grams  of  supplement  daily 4.0  per  cent  of  the  total  ration 

Eight  grams  of  supplement  daily 7.7  per  cent  of  the  total  ration 

Sixteen  grams  of  supplement  daily 14.4  per  cent  of  the  total  ration 

Thirty-two  grams  of  supplement  daily 25.2  per  cent  of  the  total  ration 

One  cubic  centimeter  of  salmon  oil  daily  is  equivalent  to  1.0  per  cent  of 
the  total  ration. 
These  amounts  represent  the  percentage  of  supplement  to  the  total  food  con- 
sumption of  healthy  chickens.     The  birds  which  sickened  consumed  less  grain  and 
mash,  therefore  the  percentage  of  supplement  in  the  total  food  consumption  of 
such  birds  was  considerably  higher. 

10  Beach,  J.  E.,  op.  cit.,  pp.  3,  4.    figs.  1-7. 


b  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

All  birds  were  weighed  and  examined  at  weekly  intervals. 
The  experimental  feeding  began  October  19  and  continued  until 
January  22,  a  period  of  ninety-six  days. 

RESULTS  OBTAINED   IN  THE   DIFFERENT  GROUPS 

Group  I — Basal  ration  phis  Yellow  Giant  carrot. 

The  amount  of  Yellow  Giant  carrot  was  maintained  at  one  gram 
daily  throughout  the  experiment.  No  lesions  of  nutritional  disease 
appeared  and  no  birds  died  from  any  cause. 

The  average  weight  of  the  birds  in  this  group  increased  from 
1105  grams  on  October  16  to  1570  grams  on  January  22,  the  close  of 
the  experiment,  a  gain  in  weight  of  42  per  cent  during  the  ninety-six 
days  of  experimental  feeding. 

Seventeen  eggs  were  produced  in  this  pen  before  the  birds  were 
six  months  of  age.  The  production  from  December  12,  the  day  the 
birds  were  six  months  of  age  (fifty-fifth  day  of  the  experiment)  until 
the  close  of  the  experiment  was  30.4  per  cent.  A  total  of  145  eggs 
was  produced. 

Group  II — Basal  ration  plus  Mammoth  Long  Red  mangel. 

The  amount  of  Mammoth  Long  Red  mangel  was  maintained  at 
one  gram  daily  until  November  27,  the  fortieth  day  of  the  experiment. 
On  this  date  two  birds,  14  and  16,  showed  pustules  and  bird  13  died. 
A  post-mortem  examination,  however,  failed  to  show  any  evidence  of 
nutritional  disease  in  bird  13.  The  amount  of  mangel  was  increased 
to  two  grams  daily  on  November  28.  On  December  4  (the  forty- 
seventy  day)  two  more  birds  (15  and  20)  showed  lesions  in  the 
esophagus.  The  amount  of  mangel  was  increased  on  December  5  to 
eight  grams  daily.  On  December  7  three  birds,  12,  14,  and  16,  died 
of  nutritional  disease.  Bird  12  showed  no  external  lesions  prior  to 
death.  On  December  11  (the  fifty-fourth  day)  one  new  case  (in 
bird  19)  of  nutritional  disease  appeared.  The  amount  of  mangel 
was  increased  to  sixteen  grams  daily  on  December  12.  Bird  19  which 
had  previously  shown  pustules  developed  ophthalmia  on  December  24 
(the  sixty-seventh  day).  The  amount  of  red  mangel  was  increased 
to  thirty-two  grams  daily  on  December  25.  This  amount  constituted 
25.2  per  cent  of  total  food  consumption  of  the  birds  and  was  more 
than  they  would  voluntarily  consume  in  two  hours.  On  December  27 
(the  seventieth  day)  bird  19  died  of  nutritional  disease  and  on 
January  6  (the  eightieth  day)  bird  15  died  from  the  same  cause. 
Birds  11  and  18  first  showed  pustules  on  December  31  (the  seventy- 


BUL.  412]        A  STUDY  OF  SOURCES  OF  VITAMIN  A  FOR  POULTRY  7 

fourth  day)  and  lesions  in  bird  17  first  appeared  on  January  15 
(the  eighty-ninth  day).  Nine  (90  per  cent)  of  the  ten  birds  in  this 
group  developed  the  lesions  characteristic  of  vitamin  A  deficiency 
and  five  (50  per  cent)  died  of  this  cause. 

The  average  weight  of  the  birds  which  survived  to  the  end  of  the 
experiment  was  1132  grams  on  October  16  and  1372  grams  on  Jan- 
uary 22,  an  increase  in  weight  of  21.2  per  cent  during  ninety-six  days 
of  experimental  feeding. 

Nineteen  eggs  were  produced  by  this  group  during  the  experiment. 

Group  III — Basal  ration  plus  Danvers  Half  Long  carrot  (red). 

The  amount  of  Danvers  Half  Long  carrot  was  maintained  at  one 
gram  daily  throughout  the  experiment.  No  lesions  of  nutritional 
disease  appeared  and  no  birds  died  from  any  cause. 

The  average  weight  of  the  birds  in  this  group  on  October  16  was 
1056  grams  and  on  January  22,  the  close  of  the  experiment,  was  1492 
grams,  an  increase  of  41.2  per  cent  in  weight  during  ninety-six  days 
of  experimental  feeding. 

Thirty-one  eggs  were  produced  in  this  pen  before  the  birds  were 
six  months  of  age.  The  production  from  December  12,  the  day  the 
birds  were  six  months  of  age  (the  fifty-fifth  day  of  the  experiment) 
until  the  close  of  the  experiment  was  33.3  per  cent.  A  total  of  171 
eggs  was  produced  during  the  experiment. 

Group  IV — Basal  ration  plus  Golden  Tankard  mangel  (yellow). 

The  first  lesions  of  nutritional  disease  in  group  IV  appeared  on 
November  20  (the  thirty-third  day)  in  bird  33.  On  November  27 
(the  fortieth  day)  lesions  appeared  in  bird  31.  The  amount  of  mangel 
was  increased  to  two  grams  daily  on  November  28.  Bird  31  died 
of  nutritional  disease  on  November  30  (the  forty-third  day).  By 
December  4  (the  forty-seventh  day)  five  new  cases  of  nutritional 
disease  (32,  35,  37,  38,  and  40)  had  developed.  The  amount  of  mangel 
for  this  group  was  increased  to  eight  grams  daily  on  December  5. 
Bird  37  died  of  nutritional  disease  on  December  8  (the  fifty-first  day) 
and  bird  35  died  on  December  10  (the  fifty-third  day)  from  the  same 
cause.  One  new  case  of  nutritional  disease  (in  bird  34)  was  found 
on  December  11  (the  fifty-fourth  day).  The  amount  of  mangel  was 
increased  to  sixteen  grams  daily  on  December  12.  On  December  18 
(the  sixty-first  day)  bird  36  showed  pustules  in  the  esophagus.  With 
the  exception  of  bird  39  all  remaining  birds  in  this  group  showed 
lesions  in  the  esophagus.  Bird  38  died  of  nutritional  disease  on 
December  23  (the  sixty-sixth  day).     On  December  25  the  amount  of 


8  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

mangels  was  increased  to  thirty-two  grams  daily.  Bird  33  died  of 
nutritional  disease  on  December  26  (the  sixty-ninth  day).  Bird  40 
died  of  nutritional  disease  on  January  2  (the  seventy-sixth  day) 
and  bird  32  died  on  January  5  (the  seventy-ninth  day).  Pustules 
had  developed  in  bird  39  on  January  8  (the  eighty-second  day).  Bird 
36  died  of  nutritional  disease  January  18  (the  ninety-second  day). 
All  of  the  birds  in  this  group  developed  symptoms  of  vitamin  A 
deficiency  and  eight  died. 

The  average  weight  of  the  birds  that  survived  to  the  end  of  the 
experiment  was  935  grams  on  October  16  and  1180  grams  on  Jan- 
uary 22,  an  increase  of  26.2  per  cent  in  weight  during  ninety-six 
days  of  experimental  feeding. 

The  birds  in  this  group  produced  no  eggs  during  the  experiment. 

Group  V — Basal  ration  plus  White  Belgian  carrot. 

The  amount  of  White  Belgian  carrot  was  maintained  at  one  gram 
daily  until  November  27  (the  fortieth  day).  Bird  43  showed  pustules 
on  this  date  and  died  on  December  1  (the  forty-fourth  day).  The 
amount  of  carrot  was  increased  to  two  grams  on  November  28.  Two 
more  birds  (42  and  49)  showed  nutritional  disease  lesions  on  Decem- 
ber 5  (the  forty-seventh  day)  and  the  daily  amount  of  carrot  was 
increased  to  four  grams.  Bird  48  showed  pustules  on  December  11 
(the  fifty-fourth  day).  On  December  18  (the  sixty-first  day)  two 
new  cases,  birds  44  and  46,  developed.  The  amount  of  carrot  was 
increased  to  eight  grams  on  December  19.  Bird  45  showed  lesions  on 
December  24  (the  sixty-seventh  day)  and  the  carrot  was  increased  to 
sixteen  grams  on  the  following  day.  Bird  42  died  of  nutritional 
disease  December  25  (the  sixty-eighth  day).  Since  sixteen  grams 
was  more  than  the  birds  would  voluntarily  consume,  the  daily  supply 
of  carrot  Avas  not  increased  above  this  amount.  Bird  44  died  of 
nutritional  disease  on  January  7  (the  eighty-first  day)  and  bird  49 
died  on  January  13  (the  eighty-seventh  day)  of  the  same  cause. 
Pustules  first  appeared  in  birds  41  and  47  on  January  8  and  15  (the 
eighty-second  and  eighty-ninth  days),  respectively. 

Four  birds  died  of  nutritional  disease,  five  showed  pustules  at 
the  close  of  the  experiment  and  one  was  apparently  in  good  health. 

The  average  weight  of  the  birds  that  survived  to  the  end  of  the 
experiment  was  1148  grams  on  October  16  and  1460  grams  on  Jan- 
uary 22,  an  increase  of  27.1  per  cent  in  weight  during  ninety-six  days 
of  experimental  feeding. 

This  group  produced  sixteen  eggs  during  the  experiment. 


BUL.  412]        A  STUDY  OF  SOURCES  OF  VITAMIN  A  FOR  POULTRY  9 

Group  VI — Basal  ration  plus  Half  Sugar  mangel  (white). 

The  first  indication  of  vitamin  A  deficiency  in  group  VI  was  the 
appearance  of  pustules  in  birds  51  and  52  on  November  20  (the  thirty- 
third  day).  Bird  55  died  of  nutritional  disease  on  November  27  (the 
fortieth  da}^  without  having  previously  shown  symptoms  of  the 
disease.  The  amount  of  mangel  was  increased  to  two  grams  daily  on 
November  28.  On  December  4  (the  forty-seventh  day)  four  more 
birds  (53,  56,  57,  and  60)  show^ed  pustules  in  the  esophagus.  The 
amount  of  mangel  was  increased  to  sixteen  grams  on  December  12. 
Birds  51,  60,  and  56  died  of  nutritional  disease  on  December  12,  15, 
and  22  (the  fifty-fifth,  fifty-eighth,  and  sixty-fifth  days),  respectively. 
Bird  54  developed  pustules  and  bird  52  ophthalmia  on  December  24 
(the  sixty-seventh  day).  The  amount  of  mangels  was  increased  to 
thirty-two  grams  daily  on  December  25.  Birds  52  and  59  died  of 
nutritional  disease  on  December  30  (the  seventy-third  day).  The 
first  pustules  in  bird  59  were  observed  on  December  24,  six  days 
before  death.  Bird  58,  the  last  bird  to  develop  lesions  of  vitamin  A 
deficiency,  show^ed  pustules  on  December  31  (the  seventy-fourth  day). 
Bird  54  died  of  nutritional  disease  January  15  (the  eighty-ninth  day). 
All  of  the  ten  birds  in  this  group  developed  nutritional  disease  and 
seven  died  from  this  cause. 

The  average  weight  of  the  birds  that  survived  to  the  end  of  the 
experiment  was  1023  grams  on  October  16  and  1233  grams  on  Jan- 
uary 22,  an  increase  of  20.5  per  cent  in  weight  during  ninety-six  days 
of  experimental  feeding. 

The  total  production  from  this  group  was  three  eggs. 

Group  VII — Basal  ration  plus  American  Purple  Top  Swede  turnip 
{yellow). 
The  amount  of  American  Purple  Top  Swede  turnip  was  maintained 
at  one  gram  daily  until  November  27  (the  fortieth  day)  when  it  was 
increased  to  two  grams  because  three  birds  (65,  66  and  67)  showed 
pustules  in  the  esophagus.  The  first  pustules  to  appear  in  this  group 
were  in  bird  65,  on  the  thirty-third  day.  On  November  27  bird  ^^, 
which  showed  pustules,  was  destroyed  by  its  mates.  The  amount  of 
turnip  was  increased  to  four  grams  on  December  5  (the  forty-eighth 
day)  when  one  new  case,  bird  63,  developed.  On  December  7  bird  61 
died.  A  post-mortem  examination  showed  a  slight  congestion  of 
urates  in  the  kidneys,  but  there  was  not  sufficient  evidence  to  warrant 
a  diagnosis  of  death  due  to  nutritional  disease.  On  December  16  (the 
fifty-ninth  day)  bird  65  died  of  nutritional  disease  and  on  December 
18  (the  sixty-first  day)  bird  70  died  of  the  same  cause.    On  December 


10  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

18  birds  69  and  64  showed  pustules.  The  amount  of  turnip  was 
increased  to  eight  grams  on  December  19.  On  December  31  bird  68 
died  of  nutritional  disease.  The  amount  of  turnip  was  increased  to 
sixteen  grams  daily  on  January  1.  Bird  64  died  of  nutritional  disease 
on  January  2  (the  seventy-sixth  day).  On  January  15  (the  eighty-ninth 
day)  bird  62,  the  last  of  this  group,  showed  pustules.  The  amount 
of  turnip  was  increased  to  thirty-two  grams  daily  on  January  16. 

Two  birds  in  this  group  (61  and  66)  died  of  causes  other  than 
nutritional  disease,  but  one  of  these  had  the  characteristic  pustules 
in  the  esophagus.  Nine  of  the  ten  birds  in  this  group  developed 
lesions  of  vitamin  A  deficiency  and  four  died  of  this  cause ;  the  four 
remaining  birds  showed  pustules  at  the  close  of  the  experiment. 

The  average  weight  of  the  birds  that  survived  to  the  end  of  the 
experiment  was  1130  grams  on  October  16  and  1147  grams  on  January 
22,  an  increase  of  1.5  per  cent  in  weight  during  ninety-six  days  of 
experimental  feeding. 

This  group  produced  seven  eggs  during  the  experiment. 

Group  VIII — Basal  ratio7i  plus  Purple  Top  White  Globe  turnip. 

On  December  7  bird  71  was  destroyed  by  its  mates.  The  first 
lesions  of  nutritional  disease  in  group  VIII  appeared  in  two  birds 
(74  and  75)  on  December  11  (the  fifty-fourth  day).  Bird  75  died  of 
nutritional  disease  on  December  14  (the  fifty-seventh  day).  Bird  73, 
which  showed  no  evidence  of  vitamin  A  deficiency  when  examined 
on  December  11,  died  of  nutritional  disease  December  17  (the  sixtieth 
day).  The  amount  of  turnip  was  increased  to  two  grams  daily  on 
December  19.  Bird  74  died  of  nutritional  disease  on  December  26 
(the  sixty-ninth  day).  Bird  79  died  December  30  (the  seventy-third 
day)  without  having  previously  exhibited  symptoms.  The  amount  of 
turnip  was  increased  on  January  1  to  four  grams  daily.  Bird  80 
showed  pustules  on  January  8  (the  eighty-second  da}^).  Birds  76 
and  78  showed  pustules  on  January  15  (the  eighty-ninth  day).  The 
amount  of  turnip  was  increased  to  eight  grams  daily  on  January  16. 
On  the  ninety-sixth  day  lesions  appeared  in  bird  77. 

One  bird  (71)  in  this  group  was  destroyed  by  mates,  four  died  of 
nutritional  disease,  four  showed  pustules  at  close  of  the  experiment 
and  one  was  apparently  in  good  health.  The  number  which  suffered 
from  nutritional  disease  was  eight,  or  80  per  cent. 

The  average  weight  of  the  birds  that  survived  to  the  end  of  the 
experiment  was  1012  grams  on  October  16  and  1250  grams  on  Jan- 
uary 22,  an  increase  of  23.5  per  cent  in  weight  during  ninety-six  days 
of  experimental  feeding. 

This  group  produced  27  eggs  during  the  experiment. 


BUL.  412]         A  STUDY   OF   SOURCES   OF   VITAMIN  A  FOR   POULTRY  11 

Group  IX — Basal  ration  plus  salmon  oil. 

The  amount  of  salmon  oil  was  maintained  at  one  cubic  centimeter 
daily  throughout  the  experiment  and  no  lesions  of  nutritional  disease 
appeared.  One  bird  (95)  died  from  ileal  intussusception  and  chronic 
coccidiosis. 

The  average  weight  in  this  group  on  October  16  was  999  grams 
and  on  January  22,  at  the  close  of  the  experiment,  was  1444  grams, 
an  increase  of  44.5  per  cent  in  weight  during  ninety-six  days  of 
experimental  feeding. 

Twenty-eight  eggs  were  produced  in  this  pen  before  the  birds  were 
six  months  of  age.  The  production  from  December  12,  the  day  the 
birds  were  six  months  of  age  (the  fifty-fifth  day  of  the  experiment) 
until  the  close  of  the  experiment  was  26.4  per  cent.  This  group 
produced  a  total  of  128  eggs  during  the  experiment. 

A  pen  of  ten  birds  to  which  mung  bean  {Phaseolus  aureus)  sprouts 
were  given  as  a  supplement  to  the  basal  ration  was  included  at  the 
beginning  of  the  experiment.  On  account  of  difficulty  in  sprouting 
the  seeds,  the  supply  of  sprouts  was  inconstant  and  no  definite  knowl- 
edge regarding  their  value  was  being  secured.  Therefore,  after  67 
days,  the  feeding  of  this  supplement  was  abandoned  and  the  daily 
administration  of  1  cc.  of  salmon  oil  to  each  bird  was  substituted. 
At  the  time  the  change  was  made,  growth  and  egg  production  of  the 
birds  had  ceased  and  six  of  them  had  the  lesions  characteristic  of 
vitamin  A  deficiency.  During  the  following  28  days  until  the  experi- 
ment was  terminated,  these  birds  entirely  recovered  from  the  effect 
of  vitamin  A  deficiency,  increased  13.1  per  cent  in  weight  and  pro- 
duced 29  eggs. 

Group  X — Basal  ration.    Controls. 

The  first  evidence  of  nutritional  disease  in  group  X  was  the  death 
from  this  cause  of  bird  106  on  November  19  (the  thirty-second  day). 
Pustules  of  nutritional  disease  appeared  in  bird  107  on  November  27 
(the  fortieth  day).  Bird  108  died  of  nutritional  disease  December  2 
(the  forty-fifth  day).  Bird  109  showed  pustules  on  December  4  (the 
forty-seventh  day)  and  on  December  11  (the  fifty-fourth  day)  nutri- 
tional disease  had  appeared  in  birds  102  and  110.  On  December  18 
(the  sixty-first  day)  bird  101  developed  pustules.  Birds  107  and  109 
died  of  nutritional  disease  on  December  20  and  22  (the  sixty-third 
and  sixty-fifth  days),  respectively.  Pustules  appeared  in  bird  103 
on  December  24  (the  sixty-seventh  day).  Bird  101  died  of  nutritional 
disease  on  December  27  (the  seventieth  day)  of  the  same  cause.    Bird 


12 


UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 


i  o  ?1 


J2  -gTJ 


3; 


I  a)  S 


03  o 


S  °  aa-§ 
■^  S  as 


2*0  g-t3 

a  o  aa-^ 


o  q 


0000 


(M        l-t        T-l        O 


O   >0    O   00   -^   t^ 


TjH      Tj<      O      CO 


O    Oi   O   O    C5   o 


O    (M    C^    (M    '-I    »0 


10  10  to  t^ 


tB 


m     m     VI 


a  s  s  s  a 

c3  o3  oj  o3  oj 

fcH  t-l  t-l  ^  ?H         S-l 

bC  bC  bC  fc>C  faC    bO 


oi 


a  a 

;h    ;h    o 

faC   faC  a 


a  a  a  a  a  a 

c3  c5  o3  c3  c3  o3 

;_  ^  ^H  !-<  M  !h 

biD  bC  bC  bC  bJO  bJO 


a  a 

bJ3    bi)    O 


■Si 


't3 
0    0^ 

IS 


^   2  Z. 
S   s^   a; 

"     03     bJO 

^a 


o3 


a 


§2 

o3     O 


•■^  ^ 

2  ^ 

g  bfl^ 
I  a,^ 

bC   sh   Ph 

(Ti      ^S      rt 

j5  03  a 
^  M  <i 


Ph   02   12; 


a  .2 


i2-  a 

I  §. 

::;   o 

cS    a; 

^  -^ 

.  ^    to 

as-? 


(B  a)    c3  ^ 

O  -tJ     o  iS 

O  o  ^  o 

O  >'-2  S 


T3 


8  1^  « 

a  g  ^  i 

3     t-     «  !> 

O    -d    •^  T3 


M  •-< 


0  X2 

01  a; 


w  o  o  o 


BUL.  412]        A  STUDY  OF  SOURCES  OF  VITAMIN  A  FOR  POULTRY  13 

105  showed  pustules  in  the  esophagus  January  8  (the  eighty-second 
day)  and  lesions  appeared  January  15  (the  eighty-ninth  day)  in 
bird  104,  the  last  bird  of  the  group. 

The  average  weight  of  the  birds  which  survived  to  the  end  of  the 
experiment  was  1040  grams  on  October  16  and  1297  grams  on  Jan- 
uary 22,  an  increase  of  24.7  per  cent  in  weight  during  the  ninety-six 
days  of  the  experiment. 

All  of  the  ten  birds  in  this  group  became  affected  with  nutritional 
disease  and  six  (60  per  cent)  died  from  this  cause. 

This  group  produced  only  two  eggs  during  the  experiment. 

A  tabulated  summary  of  results  is  given  in  table  2. 


DISCUSSION    OF   THE    EXPERIMENT 

None  of  the  birds  in  groups  I,  III,  and  IX  that  received  yellow 
carrots,  red  carrots,  and  salmon  oil,  respectively,  showed  any  evidence 
of  vitamin  A  deficiency  during  the  experiment.  One  bird  in  group  IX 
died  from  ileal  intussusception  and  upon  autopsy  was  found  also  to 
be  affected  with  chronic  coccidiosis.  All  three  of  these  groups  increased 
in  weight  from  41  to  44.5  per  cent.  The  egg  production  for  the  last 
forty-one  days  was  30.4  per  cent  in  group  I,  33.3  per  cent  in  group 
III  and  26.4  per  cent  in  group  IX. 

The  curative  value  of  salmon  oil  for  fowls  suffering  from  vitamin  A 
deficiency  was  demonstrated  by  its  effect  on  the  group  to  which  mung 
bean  sprouts  had  been  fed.  Six  birds  which  had  developed  symptoms 
of  vitamin  A  deficiency  recovered,  and  all  of  the  ten  birds  in  the 
group  increased  in  weight  and  egg  production  after  salmon  oil  was 
substituted  for  the  sprouts. 

The  results  obtained  with  White  Belgian  carrots  (group  V)  were 
decidedly  inferior  to  those  obtained  with  either  red  or  yellow  carrots. 
Increasing  the  amount  of  white  carrots  to  sixteen  grams  for  each  bird 
daily  did  not  prevent  the  development  of  symptoms  of  vitamin  A 
deficiency.  This  group  showed  a  27.1  per  cent  gain  in  weight  as 
compared  with  a  gain  of  42  and  41.2  per  cent  gain  respectively  in 
groups  I  and  III,  which  received  yellow  or  red  carrots.  Ten  eggs 
were  produced  after  these  birds  were  six  months  of  age  while  during 
the  same  period  group  I  laid  128  eggs  and  group  III  laid  140. 

Both  varieties  of  turnips  used  proved  to  be  poor  sources  of  vita- 
min A.  Although  40  per  cent  of  the  birds  in  each  group  died  of 
nutritional  disease  and  there  was  a  variation  of  only  10  per  cent  in 


14  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

the  number  of  birds  showing  lesions  in  each  group  (90  per  cent  in 
group  VII  and  80  per  cent  in  group  VIII)  there  was  a  marked 
difference  in  the  results  obtained  with  these  two  varieties  as  was 
indicated  by  a  difference  in  the  time  of  appearance  of  the  first  lesions, 
the  gain  in  weight,  and  the  egg  production  of  the  two  groups.  The 
first  lesions  of  nutritional  disease  appeared  in  group  VII  (American 
Purple  Top  Swede  turnip)  on  the  thirty-third  day  and  in  group  VIII 
(Purple  Top  White  Globe  turnip)  on  the  fifty-fourth  day,  twenty-one 
days  later.  Group  VII  increased  1.5  per  cent  in  weight  and  produced 
a  total  of  seven  eggs,  while  group  VIII  increased  23.5  per  cent  in 
weight  and  produced  a  total  of  twenty-seven  eggs.  The  fact  that  the 
amount  of  American  Purple  Top  Swede  turnip  supplied  was  increased 
to  thirty-two  grams  daily  while  in  group  VIII  the  maximum  daily 
amount  of  Purple  Top  White  Globe  turnip  was  eight  grams,  further 
emphasizes  the  difference  between  these  two  supplements. 

All  three  varieties  of  mangel  beets  used  proved  valueless  as  sources 
of  vitamin  A.  There  were  slight  differences  between  the  three  groups 
with  respect  to  the  time  of  the  first  appearance  of  lesions,  the  mor- 
tality, increase  in  weight,  and  the  egg  production,  but  all  the  birds 
in  these  groups  developed  definite  lesions  of  vitamin  A  deficiency. 

The  amount  of  these  supplements  was  increased  to  thirty-two 
grams  daily,  which  was  more  than  the  birds  would  voluntarily  con- 
sume. Following  this  increase,  there  was  no  improvement  in  the 
condition  of  the  birds  already  affected  and  nutritional  disease  lesions 
developed  in  all  those  apparently  healthy  at  the  time  the  increase 
was  made. 

All  birds  in  group  X  (control)  developed  nutritional  disease  and 
60  per  cent  died  of  this  cause. 


BUL.  412]        A  STUDY  OF  SOURCES  OF  VITAMIN  A  FOR  POULTRY  15 


h^,^ 


CONCLUSIONS 

It  is  recognized  that  the  number  of  birds  used  in  this  experiment 
was  small,  but  nevertheless  the  results  are  so  clear-cut  that  the  follow- 
ing definite  conclusions  may  be  drawn: 

(1)  The  Yellow  Giant  carrot  and  Danvers  Half  Long  carrot  (red) 
are  equal  in  value  to  the  commonly  used  varieties  of  green  feed^^  as 
sources  of  vitamin  A  for  poultry. 

(2)  The  salmon  oil  appears  to  be  as  good  a  source  of  vitamin  A 
for  poultry  as  yellow  carrots,  red  carrots,  or  the  commonly  used 
varieties  of  green  feed. 

The  salmon  oil  used  also  appears  to  compare  favorably  with 
cod-liver  oil  as  a  source  of  vitamin  A  for  poultry,  since  the  amount 
used  in  this  experiment  is  the  same  as  that  of  cod-liver  oil  used  in 
previous  experiments^^  and  as  is  commonly  recommended  to  supply 
vitamin  A  in  poultry  rations. 

(3)  The  Purple  Top  White  Globe  turnip  appears  to  contain 
some  vitamin  A,  but  is  not  a  sufficiently  good  source  to  make  it  of 
any  practical  value  in  poultry  feeding. 

(4)  The  White  Belgian  carrot,  American  Purple  Top  Swede 
urmp  (.(s^htt^ ,  Mammoth  Long  Red  mangel.  Golden  Tankard  mangel 
(yellow),  and  Half  Sugar  mangel  (white)  are  of  no  value  as  sources 
of  vitamin  A  for  poultry. 


11  Based  on  Davis,  D.  E,,  and  J.  E,  Beach,  op.  cit. 

12  Beach,  J.  E.,  op.  cit.,  p.  4. 


